Balers, specifically two ram balers, are commonly used to compress recyclable products or waste material such as aluminum cans and the like into bales and then to strap the bales in order to facilitate transportation of the materials. Examples of such two ram balers are described in U.S. Pat. No. 5,007,337, entitled "Oversize Bale Release Mechanism For Waste Material Baler" and U.S. Pat. No. 5,081,922, entitled "Device for Controlling the Discharge of a Bale from a Solid Waste Baling Machine." These balers generally comprise a hopper for storing and feeding the material to be baled and a baling chamber in which the bale is formed. A main compression ram comprising a hydraulic plunger and platen is operated within the chamber to compress the material into the shape of the bale, and a smaller ram ejects the bale into the strapping device.
Two knives or cutting edges are often used in order to separate the material in the hopper from the material in the baling chamber. One such cutting edge, the first or fixed cutting edge, is frequently attached to the top of the baling chamber adjacent where the material enters the baling chamber from the hopper. The other cutting edge, the second or movable cutting edge, is frequently attached to the top of the platen. As the hydraulic plunger extends, the top of the platen moves underneath the top of the baling chamber. Consequently, the two cutting edges meet in a scissor-type action to cut and separate material in the hopper from material in the baling chamber. It is very important for satisfactory operation of the baler to maintain minimum vertical clearance or spacing between the first and second cutting edges.
Problems arise during normal operation of the baler as various components wear, and the distance between the two cutting edges increases. As this distance increases, the cutting efficiency is reduced, much like the cutting efficiency of scissors is reduced if the connecting rivet loosens. As the cutting efficiency is reduced, total separation of the material is not accomplished. Damage to the baler may occur from forces such as those associated with the main compression ram tearing the material rather than cutting the material.
This problem has been previously solved in several ways. One technique is an adjustable top for the ceiling of the baling chamber. The top of the baling chamber is placed on shims and secured with bolts. As the bottom surface of the platen or other components wear, thus increasing the distance between the two cutting edges, the top of the baling chamber may be disassembled. A number of shims are removed to reestablish the desired vertical clearance between the two cutting edges and the top of the chamber reinstalled. Another method is to install shims underneath the floor of the baling chamber. As the bottom surface of the platen or other components wear, the number of shims is increased, thereby raising the platen and its associated cutting edge to reestablish the desired vertical clearance.
One problem with both of the above methods is that it takes substantial time and effort to disassemble the proper parts of the baler at the proper time, change the required number of shims, and then reassemble the parts of the baler. Another problem with the prior methods is that the baler operator is often not qualified to perform the required adjustments. Professional service help must then be called resulting in more down time for the baler. Even where operators are qualified to perform the adjustments, the time and effort required often results in the operators neglecting to readjust the vertical distance between the cutting edges when necessary. This neglect may result in inefficient baling or damage to the baler.